Birds navigate during migration using a combination of several innate abilities and environmental cues. These include:
- Celestial cues: Birds use the sun, stars, and the Earth's magnetic field as navigational aids to determine their position and direction.
- Smell: Birds can use their sense of smell to identify landmarks and find their way.
- Memory: Birds can store information about migration routes, including landmarks and environmental cues, and use it to guide their migration.
- Geographical features: Birds use physical features such as coastlines, rivers, and mountain ranges to orient themselves.
Overall, the exact navigation mechanism used by birds is not fully understood, but it is believed to be a combination of these and other factors.